Selection of ecological indicators to monitor the recovery of mountain wetlands in the Arid Andes

Abstract

Although mountain wetlands in the Andes are of high conservation value and provide key ecosystem services to the human populations that rely on them, they are degraded by human and natural factors like tourism, overgrazing, and climate change. Ecological restoration is an important tool to foster their recovery, but selection of indicators is crucial in order to meet monitoring requirements with limited resources. This study proposes to use a qualitative weighting matrix to select ecological indicators for monitoring restoration. We applied this methodology in a high mountain wetland in Aconcagua Provincial Park in the Arid Andes of Argentina, which is undergoing natural restoration. We surveyed 34 variables corresponding to different taxa (vegetation, vertebrates, and invertebrates) and Horcones lake water properties for the two main plant communities in the park (steppe and wetland) under different disturbance levels (absent-low, medium, and high). We weighed the variables using 10 criteria related to sensitivity to environmental change, interpretability, management, and feasibility. After weighting, 57% of the variables were selected as indicators. To retain indicators of different taxa and lake properties, we propose two monitoring frequencies: 1–2 years for indicators that can be estimated by people with only general ecological knowledge (e.g. trampling evidence and plant height) and 5 years for indicators requiring higher survey efforts and expert involvement (e.g. fauna abundance and species diversity). We conclude that the subjective weighting procedure could make the selection process easy to replicate.